The existing 7-story building located at the southwest corner of 15th Street and Union Square West was constructed in 1870 as the Tiffany and Company jewelry store. It was originally built with five floors, a full cellar level and two projecting sidewalk vault areas. Floor-to-floor heights ranged from seventeen to twenty-one feet. In 1953 the original, ornate cast-iron exterior was covered over with a new brick façade. Additional modifications occurred in 1980, including the insertion of two new mezzanine levels above the original Second and Fifth Floors and the removal of an existing column near the top of the building. New elevators and stairs were also installed. Some existing floor areas were removed and replaced. The proposed new renovation will convert the structure into luxury apartments.  Portions of the existing floors will be removed and replaced at new elevations, providing intermediate levels. As well, six new floors will be constructed on top of the building.